1689066440 has 16 divisors (see below), whose sum is σ = 3800399580. Its totient is φ = 675626560.

The previous prime is 1689066439. The next prime is 1689066443. The reversal of 1689066440 is 446609861.

It can be written as a sum of positive squares in 2 ways, for example, as 1518972676 + 170093764 = 38974^2 + 13042^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1689066391 and 1689066400.

It is not an unprimeable number, because it can be changed into a prime (1689066443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21113291 + ... + 21113370.

Almost surely, 2^1689066440 is an apocalyptic number.

1689066440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1689066440 is an abundant number, since it is smaller than the sum of its proper divisors (2111333140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1689066440 is a wasteful number, since it uses less digits than its factorization.

1689066440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42226672 (or 42226668 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 1689066440 is about 41098.2534908723. The cubic root of 1689066440 is about 1190.9190555696.

The spelling of 1689066440 in words is "one billion, six hundred eighty-nine million, sixty-six thousand, four hundred forty".